FR3024210A1 - LIGHTING DEVICE IN AQUATIC ENVIRONMENT - Google Patents

Abstract

This device comprises an electronic card (1) comprising a front surface (11), light emission means (2) mounted on the front surface (11), a protective cover arranged to protect the electronic card (1) and the emission means (2), heat transfer means arranged to transfer the heat produced by the emission means (2) to the aquatic medium, the device being remarkable in that the heat transfer means comprise a layer of thermally conductive resin (3) having a heat exchange surface (30) in direct contact with the aquatic medium, the resin layer (3) being arranged to transfer heat to the heat exchange surface (30), and the resin layer (3) is shaped to seal the protective cap with the heat exchange surface (30).

Description

The present invention relates to a lighting device in an aquatic environment.

A lighting device in an aquatic environment known from the state of the art, in particular from document EP 2 594 245, comprises: an electronic card comprising a surface, said front surface, light-emitting means mounted on the front surface of the electronic card, - a protective cover arranged to protect the electronic card and the light-emitting means, - thermal transfer means arranged to transfer the heat produced by the light-emitting means to the medium. aquatic. The heat transfer means comprise a metal plate mounted on the surface, said back, opposite to the front surface of the electronic card. The metal plate is intended to be immersed in the aquatic environment to benefit from a heat exchange with the aquatic environment to be cooled. The metal plate thus makes it possible to dissipate the heat produced essentially by the light-emitting means, such as light-emitting diodes, especially power diodes. Indeed, in the absence of heat transfer means, it is observed that the temperature of the electronic card increases sharply, which can deteriorate the electronic card and the light emitting means in case of prolonged operation of the device.

However, such a device of the state of the art is not entirely satisfactory insofar as it requires a conical seal, typically rubber, disposed between the metal plate and the protective cover, so as to prevent contacting the electronic card and the light emitting means with the aquatic medium.

However, this conical seal requires the formation of shoulders in the protective cover to create support surfaces for the seal 3024210 2. The formation of shoulders in the protective cap also causes the formation of shoulders in the metal plate. Indeed, the metal plate rests partly on the rear surface of the electronic card, and partly on the shoulders of the protective cover. Consequently, such a device of the state of the art introduces a complexity in its manufacture by specific machining of the protective cover and the metal plate. In addition, the metal platinum is subjected to the external pressure of the aquatic environment. However, the rigid metal plate transmits very significant stresses to the seal. The seal suffers compression losses due to differential expansion with the metal plate, which is detrimental in terms of service life of the seal, and hence the device. The present invention aims to remedy all or part of the aforementioned disadvantages, and relates for this purpose a lighting device in an aquatic environment, comprising: an electronic card comprising a surface, said front surface, means for transmitting light mounted on the front surface of the electronic card, 20 - a protective cover arranged to protect the electronic card and the light-emitting means, - heat transfer means arranged to transfer the heat produced by the transmitting means light to the aquatic medium, the device being remarkable in that the heat transfer means 25 comprise at least one layer of thermally conductive resin having a heat exchange surface in direct contact with the aquatic medium, the resin layer being arranged relative to the electronic card for transferring the heat produced by the light-emitting means to the s heat exchange surface, and in that the resin layer 30 is shaped relative to the protective cover to seal the protective cover with the heat exchange surface.

By "resin layer" is meant a layer made of a material based on a resin. Said material may be monocomponent or multicomponent. Said material may be used for coating or filling operations (<potting "in English). Said material may be an adhesive. By "thermally conductive" is meant a layer of resin which has a thermal conductivity adapted to dissipate the heat produced by the light-emitting means, the resin layer being able to have a relationship with the conductivity of the air greater than or equal to at 5.

It should be noted that a resin layer does not merge with a foam. Thus, such a resin layer makes it possible to ensure both: the transfer of the heat produced by the light-emitting means towards the heat exchange surface, and the sealing of the protective cap with the heat exchange surface so as to prevent the contacting of the electronic card and means of light emission with the aquatic environment. Such a device according to the invention can therefore be easily manufactured in the absence of a dedicated seal and specific machining including the protective cover. In addition, such a resin layer makes it possible to better absorb the external pressure of the aquatic medium relative to a metal plate, which makes it possible to improve the service life of the device. In one embodiment, the resin layer has a surface 25 for direct contact with the front surface of the electronic board, and the ratio of the area of said direct contact area to the area of the front surface is greater than or equal to equal to 5%, preferably greater than or equal to 10%, still more preferably greater than or equal to 20%. Thus, the fact that the resin layer is in direct contact with the front surface of the electronic board makes it possible to eliminate the air between the electronic board and the protective cover, and thereby to improve the dissipation of the current. of heat because the air is a bad thermal conductor. The area of the direct contact surface is adapted to the power of the light emitting means. In one embodiment, the resin layer extends over the entire front surface of the electronic board in direct contact.

Thus, the dissipation of the heat produced by the light emitting means is facilitated by increasing the area of the heat exchange surface. In one embodiment, the electronic board has a surface, said back surface, opposite to the front surface, the resin layer has a surface of direct contact with the back surface of the electronic board, and the ratio of the area of said direct contact surface and the area of the rear surface is greater than or equal to 5%, preferably greater than or equal to 10%, more preferably greater than or equal to 20%. Thus, for some electronic boards, for example of the SMI (Isolated Metal Substrate) type, the heat produced by the light emitting means mainly accumulates on the rear surface of the electronic board. The fact that the resin layer is in direct contact with the back surface of the electronic card allows the transfer of said heat to the heat exchange surface. In one embodiment, the electronic board has a surface, so-called rear surface, opposite to the front surface, and the resin layer extends over the entire back surface of the electronic board in direct contact. Thus, the dissipation of the heat produced by the light emitting means is facilitated by increasing the area of the heat exchange surface. In one embodiment, the heat transfer means 25 comprise a heat exchanger interposed between the electronic board and the resin layer, the heat exchanger being preferably selected from the group comprising a metal plate or a finned exchanger. Thus, the fact of inserting a heat exchanger between the electronic board and the resin layer makes it possible to reduce the thickness of the layer of resin necessary to obtain a heat exchange surface with direct contact with the aquatic environment. .

Advantageously, the resin layer is arranged to cover the heat exchanger. Thus, such a resin layer provides the additional function of protecting the heat exchanger, in particular against corrosion.

In one embodiment, the device comprises collimators arranged to collimate the light emitted by the light emitting means. Thus, it is possible to obtain lighting in the aquatic environment at great distances.

Advantageously, the device comprises through holes formed in the electronic card facing the collimators. Thus, such through holes prevent the formation of air bubbles in the resin layer from the air trapped between the collimators and the electronic card. Such through holes allow to evacuate the air.

Advantageously, the resin layer comprises a metal filler. Thus, the presence of a metal filler makes it possible to increase the thermal conductivity of the resin layer, and thereby to improve the transfer of the heat produced by the light-emitting means towards the exchange surface. thermal.

In one embodiment, the resin layer has a coefficient of expansion adapted to the coefficient of expansion of the electronic card and to the temperature of the aquatic medium so as to avoid, in particular, tearing of the light-emitting means when the device is immersed in the aquatic environment.

Thus, such a resin layer makes it possible to protect the electronic card from deformations related to the external pressure of the aquatic medium. According to one embodiment, the resin layer is made based on a casting resin selected from the group comprising polyepoxides, polyurethanes, polyesters and polysiloxanes, acrylics and methyl methacrylates.

Thus, such resins are chosen in particular for their flexibility and their thermal conductivity significantly greater than that of air. Other features and advantages will appear in the following description of various embodiments of a device according to the invention, given as non-limiting examples, with reference to the appended drawings, in which: FIG. an exploded perspective view of a first device according to the invention prior to formation of the resin layer; - FIG. 2 is a perspective view of the device illustrated in FIG. 1; FIG. 3 is a perspective view. of the device illustrated in Figure 1 after the formation of the resin layer, - Figure 4 is a perspective detail view of the device shown in Figure 3 - Figure 5 is a partial sectional view on an enlarged scale of a second device according to the invention, - Figure 6 is a partial sectional view of a third device according to the invention - Figure 7 is a partial sectional view of a fourth device according to the invention , 20 - l FIG. 8 is a sectional view of a fifth device according to the invention, FIG. 9 is a sectional view of a sixth device according to the invention, FIG. 10 is a sectional view of a variant. of the sixth device 25 according to the invention, - Figure 11 is a sectional view of a seventh device according to the invention, - Figure 12 is a sectional view of an eighth device according to the invention, - the FIG. 13 is a sectional view of a ninth device according to the invention, FIG. 14 is a sectional view of a tenth device according to the invention, FIG. 15 is a partial sectional view of a FIG. Eleventh device according to the invention, - Figure 16 is a sectional view of a twelfth device according to the invention, - Figure 17 is a sectional view of a thirteenth device according to the invention, - Figure 18 is a sectional view of a variant of the ninth device 10 illustrated in FIG. 13; FIG. 19 is a sectional view of a fourteenth device according to the invention. For the various embodiments, the same references will be used for identical elements or ensuring the same function, for the sake of simplification of the description. The first device illustrated in FIGS. 1 to 4 is a lighting device in an aquatic environment, comprising: an electronic card 1 comprising a surface, said front surface 11, light emitting means 2, preferably of the diode type 20, mounted on the front surface 11 of the electronic card 1, - a protective cover 4 arranged to protect the electronic card 1 and the light emission means 2, - heat transfer means arranged to transfer the heat produced. by the light emission means 2 to the aquatic medium.

The electronic card 1 comprises a control circuit of the light emission means 2. The electronic card 1 preferably has the shape of a disk. By way of non-limiting example, the electronic card 1 may also have the shape of a parallelepiped. The front surface 11 of the electronic card 1 is advantageously flat. The front surface 11 of the electronic card 1 is preferably circular. The electronic card 1 may be made of a material which is a good thermal conductor in order to uniformly distribute the heat produced by the light emitting means 2 to the front surface 11 of the electronic card 1. The front surface 11 of the An electronic card 1 may have a coating adapted to reflect light and / or heat to increase the heat transfer to the heat exchange surface 30. The light emitting means 2 can be distributed to the front surface 11 of the electronic card 1 so as to avoid a local concentration of heat. Thus, the distances between two adjacent areas of the front surface 11 occupied by the light emitting means 2 may be substantially identical. The device comprises collimators 310 arranged on the front surface 11 of the electronic card 1 to collimate the light emitted by the light emitting means 2. The collimators 310 may be interconnected by branches 311 so as to form a network 31 of collimators 310. Such collimators 310 network are simple to install. The network 31 of collimators 310 is preferably made of a plastic material. The network 31 of collimators 310 may be equipped with an optics adapted to allow light patterns such as color mixing. The collimator array 31 occupies an area of the front surface 11 of the electronic card 1. The protective cap 4 is a hemispherical half-shell which can be made of a plastics material. Other forms for the protective cover 4 are of course possible. The protective cover 4 delimits an enclosure inside which the electronic card 1 is arranged.

The heat transfer means comprise a thermally conductive resin layer 3 having a heat exchange surface 30 in direct contact with the aquatic environment. The resin layer 3 is arranged relative to the electronic card 1 to transfer the heat produced by the light emission means 2 to the heat exchange surface 30. More precisely, the resin layer 3 extends over the complementary area of the front surface 11 of the electronic card 1 in direct contact. By "supplementary 3024210" is meant the mathematical meaning of the term; the front surface 11 of the electronic card is a set, the area occupied by the network 31 of collimators 310 is a part of this set and the complement of said occupied area (called complementary area) is the set of elements of the surface before 11 of the electronic card 1 not belonging to said occupied zone. The resin layer 3 is shaped relative to the protective cover 4 to seal the protective cover 4 with the heat exchange surface 30. The resin layer 3 may comprise a metal charge. The resin layer 3 advantageously has a coefficient of expansion adapted to the coefficient of expansion of the electronic card 1 and to the temperature of the aquatic medium so as to avoid, in particular, tearing of the light emitting means 2 when the device is immersed in the aquatic environment. The resin layer 3 may be transparent, translucent or opaque in the visible range.

The resin layer 3 is preferably made from a casting resin selected from the group consisting of polyepoxides, polyurethanes, polyesters, polysiloxanes, acrylics and methyl methacrylates.

In the embodiment illustrated in FIG. 5, the second device differs from the first device in that it comprises through holes 12 formed in the electronic card 1 facing the collimators 310 so as to evacuate the air A trapped between the collimators 310 and the electronic card 1.

In the embodiment illustrated in FIG. 6, the third device differs from the first device in that it has no collimators, and in that the resin layer 3 extends over the entire front surface 11 of the device. electronic card 1 in direct contact. The resin layer 3 is transparent or translucent in the visible range. The resin layer 3 is preferably made from a casting resin selected from the group consisting of polyurethanes and polysiloxanes. Thus, such resins can combine an excellent transmission of light and a thermal conductivity significantly higher than that of air, the ratio being greater than 7.

In the embodiment illustrated in FIG. 7, the fourth device differs from the first device in that it has no collimators. The protective cover 4 comprises optics 40 that can be made of glass or a transparent or translucent plastic material in the visible range. The optics 40 are arranged opposite the light emission means 2. The optics 40 of the protective cover 4 occupy an area of the front surface 11 of the electronic card 1. The resin layer 3 extends over the complementary area of the front surface 11 of the electronic card 1 in direct contact. By "complementary" is meant the mathematical meaning of the term; the front surface 11 of the electronic card is a set, the zone occupied by the optics 40 of the protective cover 4 is a part of this set and the complement of said occupied area (called complementary area) is the set of elements of the front surface 11 of the electronic card 1 not belonging to said occupied zone. The complementary zone forms a central zone between the optics 40 and a peripheral zone between the protective cover 4 and the optics 40. In the embodiment illustrated in FIG. 8, the fifth device differs from the fourth device in that the cover 4 comprises an optical 40 arranged facing the light emission means 2. The optic 40 occupies a central zone of the front surface 11 of the electronic card 1. The resin layer 3 extends over the peripheral zone complementary to the front surface 11 of the electronic card 1 in direct contact.

In the embodiment illustrated in FIG. 9, the sixth device differs from the first device in that the protective cover 4 comprises an optical 40 which can be made of glass or of a transparent or translucent plastic material in the visible range. The optics 40 is arranged opposite the light emission means 2. The electronic card 1 comprises a surface, said rear surface 13, opposite to the front surface 11, and the resin layer 5 extends over the entire rear surface 13 of the electronic card 1 in direct contact. The electronic card 1 comprises control circuits 6 of the light emission means 2. The control circuits 6 are arranged on the front surface 11 of the electronic card 1. FIG. 9 also shows a connection wire 7 to the electronic card 1. This embodiment is particularly suitable for an electronic card 1 of the SMI type. (Isolated Metallic Substrate), the heat produced by the light emitting means 2 accumulating mainly at the rear surface 13 of the electronic board 1. In the embodiment illustrated in FIG. 10, the control circuits 6 are arranged on the rear surface 13 of the electronic card 1 and are encapsulated in the resin layer 3. In the embodiment illustrated in FIG. 11, the seventh device differs from the modes illustrated in FIGS. 9 and 10 in that the means The heat exchanger comprises a heat exchanger 5 interposed between the electronic card 1 and the resin layer 3. The heat exchanger 5 is a metal plate extinguished ndant over the entire rear surface 13 of the electronic card 1 in direct contact. The resin layer 3 is arranged to cover the metal plate.

In the embodiment illustrated in FIG. 12, the eighth device differs from the first device in that the protective cover 4 comprises an optic 40 that can be made of glass or of a transparent or translucent plastic material in the visible range. The optics 40 is arranged facing the light emitting means 2. The electronic card 1 comprises a surface, called the rear surface 13, opposite to the front surface 11. The electronic card 1 comprises control circuits 6 of light emitting means 2. The control circuits 6 are arranged on the front surface 11 of the electronic card 1. The protective cover 4 has portions occupying peripheral zones of the rear surface 13 of the electronic card 1. The control circuits 6 can also be arranged on said peripheral zones of the rear surface 13 of the electronic card 1. The heat transfer means comprise a heat exchanger 5, of platinum metal type, extending over a central portion of the rear surface 13 of the electronic card 1 The resin layer 3 is arranged to cover the metal platen. The resin layer 3 is shaped to interpose between the metal plate and said parts of the protective cover 4 so as to seal the protective cover 4 with the heat exchange surface 30 of the resin layer 3. The heat exchange surface 30 is flush with said parts of the protective cover 4.

In the embodiment illustrated in FIG. 13, the ninth device differs from the first device in that the protective cover 4 comprises optics 40 that can be made of glass or of a transparent or translucent plastic material in the visible range. The optics 40 are arranged facing the light emitting means 2. The optics 40 of the protective cover 4 occupy a peripheral zone of the front surface 11 of the electronic card 1. The heat transfer means comprise a heat exchanger 5, of the platinum metal type, extending over a central part of the surface before 11 of the electronic card 1. The resin layer 3 is arranged to cover the metal plate. The resin layer 3 is shaped to interpose between the metal plate and said optics 40 of the protective cover 4 so as to seal the protective cover 4 with the heat exchange surface 30 of the resin layer 3 The heat exchange surface 30 is flush with said optics 40 of the protective cap 4.

In the embodiment illustrated in FIG. 14, the tenth device differs from the first device in that the protective cover 4 comprises an optic 40 that can be made of glass or a transparent or translucent plastic material in the visible range. The optics 40 is arranged in relation to the light emission means 2. The optics 40 occupy entirely the front surface 11 of the electronic card 1. The heat transfer means comprise a heat exchanger 5, of the platinum metal type, mounted on the protective cap 4 so as to extend over the entire surface rear 13 of the electronic card 1 in direct contact. The resin layer 3 rests on the metal platen. The resin layer 3 is shaped to interpose between the optic 40 and the protective cap 4 so as to seal the protective cap 4 with the heat exchange surface 30 of the resin layer 3.

In the embodiment illustrated in FIG. 15, the eleventh device differs from the first device in that the protective cover 4 comprises optics 40 that can be made of glass or of a transparent or translucent plastic material in the visible range. The optics 40 are arranged opposite the light emission means 2. The heat transfer means comprise a heat exchanger 5, of the platinum metal type, mounted on the protective cover 4 so as to extend over the entire rear surface 13 of the electronic card 1 in direct contact. The resin layer 3 rests on the metal plate in the central part. The resin layer 3 is shaped to interpose between the optics 40 so as to seal the protective cap 4 with the heat exchange surface 30 of the resin layer 3. In the embodiment illustrated in FIG. 16, the twelfth device differs from the first device in that a resin layer 3 extends over the entire rear surface 13 of the electronic card 1 in direct contact.

In the embodiment illustrated in FIG. 17, the thirteenth device differs from the sixth device illustrated in FIG. 9 in that the protective cover 4 comprises a half-shell on which the optics 40 are mounted. shell is arranged facing the resin layer 3. The half-shell is provided with orifices 8 adapted to allow the entry of water from the aquatic environment in the enclosure 9 delimited by the half-shell. Thus, the resin layer 3 has a heat exchange surface 30 with direct contact with the aquatic environment.

In the embodiment illustrated in FIG. 18, variant of the ninth device illustrated in FIG. 13, the heat exchanger 5 is of the U-shaped exchanger type. In the embodiment illustrated in FIG. 19, the fourteenth The device differs from the thirteenth device illustrated in FIG. 17 in that a heat exchanger 5, of the U-shaped exchanger type, is interposed between a central zone of the rear surface 13 of the electronic card 1 and the resin layer. 3. According to an alternative embodiment of the fourteenth device (not shown), the heat exchanger 5 is a metal plate 20 interposed between the rear surface 13 of the electronic card and the resin layer 3. A manufacturing method of the first device comprises a molding step based on the thermally conductive resin on the zone 25 complementary to the front surface 11 of the electronic card 1. The collimators 310 can have means for locking in translation of the resin in the direction perpendicular to said front surface 11 in case of overmolding above the collimators 310. It may be advantageous to form a resin thickness lower than the height of the collimators 310.

Claims (12)

REVENDICATIONS1. Lighting device in an aquatic environment, comprising: - an electronic card (1) comprising a surface, said front surface (11), - light emission means (2) mounted on the front surface (11) of the card electronics (1), - a protective cover (4, 40) arranged to protect the electronic card (1) and the light emission means (2), - heat transfer means arranged to transfer the heat produced by the means for transmitting (2) light towards the aquatic medium, the device being characterized in that the heat transfer means comprise at least one thermally conductive resin layer (3) having a contact heat exchange surface (30) direct with the aquatic medium, the resin layer (3) being arranged relative to the electronic card (1) for transferring the heat produced by the light emission means (2) towards the heat exchange surface (30), and in that the layer of r sine (3) is shaped relative to the protective cap (4, 40) for sealing the protective cover (4, 40) with the heat exchange surface (30). 2. Device according to claim 1, characterized in that the resin layer (3) has a surface of direct contact with the front surface (11) of the electronic card (1), and in that the ratio between the area of said direct contact surface and the area of the front surface (11) is greater than or equal to 5%, preferably greater than or equal to 10%, still more preferably greater than or equal to 20%. 3. Device according to claim 1, characterized in that the resin layer (3) extends over the entire front surface (11) of the electronic card (1) in direct contact. 3024210 16 4. Device according to one of claims 1 to 3, characterized in that the electronic card (1) comprises a surface, said rear surface (13), opposite the front surface (11), in that the resin layer (3) has a surface in direct contact with the rear surface (13) of the electronic board (1), and in that the ratio between the area of said direct contact area and the area of the rear surface ( 13) is greater than or equal to 5%, preferably greater than or equal to 10%, more preferably greater than or equal to 20%. 5. Device according to one of claims 1 to 3, characterized in that the electronic card (1) comprises a surface, said rear surface (13), opposite to the front surface (11), and in that the layer of resin (3) extends over the entire rear surface (13) of the electronic card (1) in direct contact. 6. Device according to one of claims 1 to 5, characterized in that the heat transfer means comprise a heat exchanger (5) interposed between the electronic card (1) and the resin layer (3), the heat exchanger (5) being preferably selected from the group comprising a metal plate or a U-shaped fin heat exchanger. 7. Device according to claim 6, characterized in that the resin layer (3) is arranged to cover the heat exchanger (5). 8. Device according to one of claims 1 to 7, characterized in that it comprises collimators (310) arranged to collimate the light emitted by the emission means (2) of light. 9. Device according to claim 8, characterized in that it comprises through holes (12) formed in the electronic card (1) facing the collimators (310). 3024210 17 10. Device according to one of claims 1 to 9, characterized in that the resin layer (3) comprises a metal filler. 11. Device according to one of claims 1 to 10, characterized in that the resin layer (3) has a coefficient of expansion adapted to the coefficient of expansion of the electronic card (1) and the temperature of the aquatic environment. in such a way as to avoid, in particular, tearing of the light emission means (2) when the device is immersed in the aquatic medium. 10 12. Device according to one of claims 1 to 11, characterized in that the resin layer (3) is made based on a casting resin selected from the group comprising polyepoxides, polyurethanes, polyesters, polysiloxanes , acrylics and methyl methacrylates. 15